few indoor growing questions

i am setting up a indoor grow closet . it is 9 feet long and 4 feet wide . i have two sets of light one for veg and one for flowering . i also have two ac units to keep the rooms cool and mylar for the walls . i am getting ready to start to rip out the old wood and stuff and build the room so no light from the outside will get in . so here is my questions

1. do i need a co2 tank for the room and why if so
2. do i need to pump in fresh air from outside . my thought on that was in the summer time i would be pumping in pollin .

thanks for the help on this .........

Alot of times if ya pump air out fresh will come in on its own.

mrweedster said:

i
1. do i need a co2 tank for the room and why if so
2. do i need to pump in fresh air from outside . my thought on that was in the summer time i would be pumping in pollin...

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1. no, it helps speed growth but not required. wait for your second grow.

2. no. most rooms are leaky enough to draw air in. if its more sealed, you can cut a passive intake (hole) in your walls. make sure to make it lightproof.

it will indeed. if i unplug my air intake but leave the exhaust running the intake fan will still spin but at a slower rate. if you have a box in the closet tho you still need to get fresh air into the closet.

best of luck mrweedster